Chapter 21, Problem 44P

Devise a synthesis of valproic acid $\left[{\left({\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}\right)}_{\text{2}}{\text{CHCO}}_{\text{2}}\text{H}\right]$, a medicine used to treat epileptic seizures, using the malonic ester synthesis.